I have seen information that the timekeeping function ranks fourth in the functional complexity of mechanical watches, second only to the timepiece, perpetual calendar and tourbillon. Although I have not personally developed a chronograph myself, I have a certain understanding of the internal structure of the chronograph. This technology also has a legendary history, and its birth also relied on watchmakers who constantly challenged themselves.
The mechanical mechanism of the chronograph function can measure a certain period of time you need to remember. On its dial, there are chronograph seconds hand, chronograph minute hand, chronograph hour hand and even two chronograph seconds hand. They are started by the button set on the outer edge of the watch , Stop and return to the complete timing function, this type of mechanical watch is often called a chronograph.
Historical background of the chronograph
Graham, a British chronologist and mechanic, first made a mechanism that can display a fraction of a second. The mechanism starts the pointer at the beginning of the measured period and stops the pointer at the end of the period. This is not yet a watch, but according to his merit, it is enough to be called the ‘father of the chronograph’. The invention of the true chronograph was due to the Parisian watchmaker-Rieussec, who created the chronograph in 1822. This watch can be used to record time periods. The first chronograph uses the ink on the dial to record time. The second hand consists of two parts that are stacked on top of each other. The lower part has a small ink reservoir. During work, bring down a pointed needle and use the ink to drop a small drop of ink on the dial. Before using this form of chronograph, the time period measured by other mechanisms that can start or stop the hands at will is not very easy. long.
Appearance of chronograph
1. Timing function buttons located at 2 o’clock and 4 o’clock of the chronograph. Of course, they may be on the right hand side, or they may be rare on the left hand side. Of course, they have also evolved timing buttons at the same time.
2. The thin and long center of the chronograph dial is the chronograph second hand, which is directly controlled by the chronograph mechanism. The start, stop and return of this chronograph second hand are completely controlled by two chronograph buttons. In addition, in order to match the chronograph function, the scale of the bezel is also subdivided into fractions of a second, generally 1/5 seconds, while the higher is 1/10 seconds, and the higher is 1/100 seconds. It has been increased to 1/1000, or even 5/10000.
3. The chronograph second hand located at the center is generally one. If it is two, then what you see is an upgraded version of the chronograph-double chase chronograph. The essence of this type of chronograph is that there are two sets of timing mechanisms. The purpose is to be able to record multiple time periods, the functionality of which surpasses the single-hand chronograph, but the difficulty of the mechanism doubles;
4. There are usually two or three small dials on the chronograph dial. Their function is to display the small second hand for normal running time, the chronograph minute hand linked with the chronograph second hand, and the chronograph hour hand display.
Internal mechanism characteristics of chronograph
1. Timing wheel: It is the hub of the timing function. It realizes the three basic functions of starting, stopping and returning to the chronograph. So what is the so-called timing wheel? There are currently two most commonly used-cylindrical star timing wheels and cam combined timing wheels. The former is used by many well-known brand chronometers. Its biggest advantage lies in the one-piece structure. The upper part is responsible for executing the commands conveyed by the button lever to direct how the timing mechanism levers should work. Star gears that play a role in driving the timing function in cooperation with the lever. The latter application is the most classic of ETA’s 7750. It is a function of commanding the timing lever to start timing through the superposition of multi-layer cams and lever springs. The difference between the two should be three-dimensional management and control, while the latter is planar control.
2. Peach-shaped cam: This cam is set on the chronograph wheel, scoring wheel and chronograph wheel. Its shape is very similar to a peach, hence its name, so why was it designed to have this shape? In fact, this is entirely based on the principle of the timing mechanism. The arcs on both sides of the wheel are symmetrical and a slightly recessed ‘butt’ is formed at the end. When the timing function is not activated, the front end of the zero-return lever is pressed on the ‘butt’ of the peach cam, so that the timing hands are at the zero position. When the timing function is activated, the timing hand starts to calculate the time. The peach cam They stayed quietly, ready to go back to zero to ‘span’ at any time, so that several chronograph hands quickly returned to zero.
The brand TAG Heuer has its own advantages and tradition in chronographs. In recent years, TAG Heuer has introduced the MIKROTIMER Flying series of high-frequency chronograph watches based on the technical advantages brought by high technology. This watch is quite original, the most obvious is to separate the time drive chain and the chronograph drive chain, so that the two do not interfere with each other to make up for the shortcomings of traditional chronographs. Not only separate the main transmission gear train from the timing transmission gear train, but also set up two different speed control mechanisms for the two gear train chains (the left picture shows the timing function speed adjustment mechanism, and the right picture shows the movement time speed adjustment mechanism). Come to serve the normal movement and timing functions of the movement. Their isolation can eliminate the interference between timing and travel time. More importantly, this design is beneficial to reduce energy loss and improve the stability of the energy input of the timing function. Thanks to this technology, TAG Heuer has improved the timing accuracy from 1 / 100th of the start to 1 / 1000th of a year until this year’s 1 / 2000th of a second.
High-frequency chronograph double speed regulating mechanism
TAG Heuer High Frequency Timing
Considering that it is too long for everyone to read, it will be boring to read, so I will divide it into two articles for you to explain. For more information about the technical analysis of TAG Heuer UHF chronograph watch, please pay attention to my next article. (Picture / Text Watch House Extension)